Inorganic/organic complexes for reducing skin irritation

ABSTRACT

β-Diketone/hydroxylated or carbonated activated cation inorganic/organic complexes are well suited for preventing, avoiding or reducing skin irritation, notably that elicited by exposure to irritant active agents/species or to the external environment.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional of application Ser. No.09/671,627, filed Sep. 28, 2000, now allowed, incorporated by referenceherein in its entirety and relied upon, which claims priority under 35U.S.C. §119 of FR-99/12057, filed Sep. 28, 1999, hereby expresslyincorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Technical Field of the Invention

[0003] The present invention relates to a method or regime/regimen forreducing skin irritation, notably that irritation attributed to thetopical application of certain active species onto the skin, or due toexposure to the environment.

[0004] This invention especially relates to reducing skin irritation bytreating the skin with effective amounts of certain inorganic/organiccomplexes, or compositions comprised thereof.

[0005] 2. Description of the Prior Art

[0006] A wide variety of compounds are formulated into cosmetics to,inter alia, improve the appearance of the skin, to beautify the skin, totreat skin conditions, or to render the skin less dry or more supple.Unfortunately, certain of these compounds may cause irritation when theyare topically applied onto the skin or mucous membranes.

[0007] It is known to this art to administer salicylic acid derivativesas keratolytic agents for treating acne; these are also usefulanti-aging agents in cosmetic and/or dermatological compositions. Thus,FR-A-2581542 and EP-A-0378936 describe such salicylic acid compounds.

[0008] Salicylic acid derivatives are of great value, given theirbiological effects on the skin, in particular on the principal clinicalsigns of skin aging, namely, fine lines and wrinkles, disorganization ofthe “grain” of the skin, modification of the skin's complexion and lossof skin firmness and tonicity. However, administration of thesederivatives presents a problem since they can cause stinging, itchingand tautness after they have been applied, which may result inconsiderable discomfort. Users, and more particularly those havingsensitive skin, are thus often discouraged from using these compounds.Sensitive skin and the signs which are characteristic of sensitive skinare described in EP-0680749.

[0009] The same also holds true for exfoliants such as hydroxy acids.Concerning these compounds, it has been proposed, in EP-0413528, tocombine them with amphoteric species in order to decrease the discomfortthat they may cause.

[0010] It is also widely described that some users of cosmetic productscomprising surfactants, preservatives, fragrances, solvents orpropellants complain that their skin is irritated after applying one ormore of the above substrates thereto.

[0011] However, because of their irritant nature, these products aregenerally employed at very low doses. Formulation of these products insmall amounts may, therefore, prove to be relatively disadvantageouswith respect to administration of other active species which are lessactive, but which are formulated in greater amounts since they are lessor not irritant.

[0012] It is also known to this art that the skin of certain individualsis irritated when it has been exposed to a specific or unusual chemicalor physical environment, in particular when it is exposed toconsiderable variations in temperature, to wind or to a very pollutedenvironment. Thus, the skin may react with itching, tautness orstinging.

[0013] Thus, the irritation may be characterized by stinging, itching ortautness, which too may cause considerable discomfort.

[0014] WO-A-96/19184, WO-A-96/19182 and WO-A-96/19228 describe theadministration of water-soluble divalent strontium, manganese, magnesiumand calcium salts to reduce the irritation of compounds which have anirritant effect, in particular of exfoliants such as hydroxy acids.

SUMMARY OF THE INVENTION

[0015] It has now unexpectedly and surprisingly been determined thatcertain inorganic/organic complexes are useful for reducing theirritation induced, in particular, by certain species or productstopically applied onto the skin, or by exposure to the environment.

[0016] Briefly, the present invention featurestherapeutically/cosmetically treating skin irritation by topicalapplication onto the afflicted skin of at least one compound having theformula (I):

[0017] in which the radicals R, which may be identical or different, areeach a linear or branched, saturated or unsaturated, optionallyhydroxylated alkyl or perfluoroalkyl radical having from 1 to 12 carbonatoms; the radicals R′, which may be identical or different, are each alinear or branched, saturated or unsaturated, optionally hydroxylatedalkyl, alkoxy or perfluoroalkyl radical having from 1 to-12 carbonatoms; and X is an element selected from among magnesium, strontium,barium, zinc, manganese, palladium and copper.

[0018] The subject compounds of formula (I) are either in hydrated ornonhydrated state and, advantageously, constitute organic/inorganiccomplexes.

[0019] The present invention thus also features a cosmetic method orregime/regimen comprising topically applying onto the skin, the keratinfibers, the nails, or the mucous membranes, at least one compound offormula (I) or composition comprised thereof.

[0020] Too, this invention features formulating at least one compound offormula (I):

[0021] in which the radicals R, which may be identical or different, areeach a linear or branched, saturated or unsaturated, optionallyhydroxylated alkyl or perfluoroalkyl radical having from 1 to 12 carbonatoms; the radicals R′, which may be identical or different, are each alinear or branched, saturated or unsaturated, optionally hydroxylatedalkyl, alkoxy or perfluoroalkyl radical having from 1 to 12 carbonatoms; and X is an element of column IIA of the Periodic Table (CASversion), zinc, manganese, palladium or copper, whether hydrated ornonhydrated, into a topically applicable, physiologically acceptablemedium (vehicle, diluent or carrier) and thus producing a dermatologicalor pharmaceutical composition, effective as an agent which reduces skinirritation.

[0022] The subject compounds/compositions are particularly usefulsoothing agents and can be formulated as cosmetic products.

DETAILED DESCRIPTION OF BEST MODE AND SPECIFIC/PREFERRED EMBODIMENTS OFTHE INVENTION

[0023] More particularly, according to the present invention, by “linearor branched alkyl radical having from 1 to 12 carbon atoms” areespecially intended methyl, ethyl, propyl, isopropyl, butyl, tert-butyl,hexyl, 2-ethylhexyl, octyl, nonyl, dodecyl, 2-methylbutyl,2-methylpentyl, 1-methylhexyl and 3-methylheptyl radicals.

[0024] Preferably, R is a linear or branched, saturated alkyl orperfluoroalkyl radical having from 1 to 6 carbon atoms. In addition, R′is advantageously a linear or branched, saturated alkyl, alkoxy orperfluoroalkyl radical having from 1 to 6 carbon atoms.

[0025] Preferably, the substituents R and R′ are linear and/orsaturated.

[0026] In particular, the substituents R and R′ preferably comprise adifference of at most two carbon atoms with respect to each other.

[0027] These compounds of formula (I) are water-insoluble, unlike thecompounds described in WO-A-96/19184, WO-A-96/19182 and WO-A-96/19228.Their property of reducing the irritation which is, in particular,induced by certain products applied onto the skin, which are generallyhydrophilic, such as hydroxy acids, is thus all the more surprising.

[0028] Exemplary derivatives according to the invention includestrontium 2,4-pentanedionate,bis(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionato)strontiumhydrate, bis(2,2,6,6-tetramethyl-3,5-heptanedionato)strontium hydrate,strontium hexafluoroacetylacetonate, calcium 2,4-pentanedionate,bis(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionato)calcium,calcium hexafluoroacetylacetonate dihydrate, calcium2,2,6,6-tetramethyl-3,5-heptanedionate, and mixtures thereof.

[0029] Certain of these compounds have been described as catalysts ofchemical reactions or as reagents of methods for obtaining inorganiccompounds, such as superconductors (WO 91/13051 or “Preparation andproperties of beta-diketone and beta-keto ester complexes of bismuth(III), strontium (II) and calcium (II)” by Doi Masura et al., in NipponKagaku Kaishi (1995), (10), 802-8).

[0030] Preferably, the substituents R and R′ are methyl radicals.

[0031] Advantageously, X is selected from among strontium, calcium,magnesium, manganese, barium, copper, zinc and palladium, and moreespecially is selected from among strontium, calcium, copper and zinc.

[0032] The compositions according to the invention are well suited fortopical application onto the skin, keratin fibers, nails or mucousmembranes; in particular, the subject compositions are cosmetic and/ordermatological compositions.

[0033] By the expression “physiologically acceptable medium” is intendeda medium which is compatible with the skin, mucous membranes (includingthe inside of the eyelids and the lips), nails and/or keratin fibers(head hair and/or body hairs). In addition, this physiologicallyacceptable medium contains no reaction by-product or residual product,since the compounds of formula (I) are the result of a clean synthesistechnique.

[0034] Specifically, these compounds are prepared via a method employinga carbonated or hydroxylated activated cation which will react with aβ-diketone (the starting organic compound). The reaction by-productsformed during the reaction are carbon dioxide or water, and they areeliminated from the reaction medium, in particular, in the form of gasor are easily eliminated after reaction (in particular with the washingwater). Furthermore, if these reaction by-products remain present intrace amounts, they are nontoxic and/or nonreactive with respect to thecompounds of formula (I).

[0035] Thus, the present invention also features compositions in whichthe compound of formula (I) is the result of the reaction between aP-diketone and a hydroxylated or carbonated activated cation.

[0036] The compounds of formula (I) according to the invention areadvantageously present in an effective amount to ensure the desiredresult, i.e., to reduce or eliminate the irritation. They can be, forexample, present in a composition according to the invention in a weightamount advantageously ranging from 0.001% to 30%, preferably from 0.01%to 20% and more preferably from 0.1% to 10%, of the total weight of thecomposition.

[0037] The compositions containing a compound according to the inventioncan be in any pharmaceutical form normally employed, and, in particular,one which is suitable for topical application, for example in the formof an oily solution, an oily gel, a liquid, pasty or solid anhydrousproduct, an emulsion of the water-in-oil (W/O), oil-in-water (O/W) ormultiple (W/O/W or O/W/0) type, a microemulsion or a vesicle dispersionof ionic and/or nonionic type. These compositions are formulatedaccording to the usual techniques.

[0038] As indicated above, the compounds of formula (I) are moreparticularly in the fatty phase of the compositions according to theinvention.

[0039] These compositions can be more or less fluid and can have theappearance of a white or colored cream, an ointment, a milk, a lotion, aserum, a paste or a mousse. They can optionally be applied onto the skinin the form of an aerosol. They can also be in solid form and, forexample, in stick form.

[0040] The subject compositions can also comprise at least one additiveor adjuvant selected from among water, fatty substances, preservatives,gelling agents, surfactants and emulsifiers, antioxidants, fillers,solvents, fragrances, dyestuffs, and colorants, UV-screening agents,cosmetic and/or dermatological active agents such as moisturizers,vitamins and anti-aging active agents, and mixtures thereof. The amountsof these various additives and adjuvants are those conventionally usedin the cosmetic and/or dermatological field.

[0041] The fatty substances can be selected from among synthetic oils,oils of animal origin, oils of plant origin, mineral oils (liquidpetroleum jelly), silicone oils, fluoro oils, and mixtures thereof.Fatty alcohols, fatty acids and waxes can also be used.

[0042] When the composition is formulated as an emulsion, the proportionof the fatty phase can range from 5% to 80% by weight, and preferablyfrom 5% to 50% by weight, relative to the total weight of thecomposition. The oils, waxes, emulsifiers and co-emulsifiers included inthe composition in emulsion form are selected from among thoseconventional in the cosmetic field. The emulsifier and the co-emulsifierare advantageously present in the composition in a proportion rangingfrom 0.3% to 30% by weight, and preferably from 0.5% to 20% by weight,relative to the total weight of the composition.

[0043] When the composition is an oily gel or solution, the fatty phasecan represent more than 90% of the total weight of the composition.

[0044] Representative emulsifiers according to the invention include,for example, polyethylene glycol oleyl ethers such as the productsmarketed under the trademarks BRIJ92 and BRIJ96 by ICI.

[0045] The amounts of the various constituents of the compositionsaccording to the invention are those conventional in the fields underconsideration. The nature of the additives and adjuvants and theiramounts should be such that they do not modify the properties of thecompounds of formula (I) according to the invention.

[0046] The compositions of the invention can be used as cleansing,protective, treatment or care products and/or as makeup products forfacial and/or body skin, mucous membranes and/or keratin fibers. They inparticular constitute treatment or care creams for the face, for thehands or for the body (for example day creams, night creams, antisun orsunscreen creams), protective or care body milks, lotions (cleansinglotions, antisun or sunscreen lotions), skincare mousses or gels, orbath compositions. They can also constitute makeup products, inparticular, for the cheeks, the lips, the eyelashes and the eyelids,such as foundations, lipsticks and eyeshadows: to this end, they cancontain dyestuffs and in particular chemical dyes or pigments.

[0047] They can also be used for the hair in the form of solutions,creams, gels, emulsions or mousses, and in particular as haircarecompositions such as shampoos, treating lotions, restructuring lotionsfor the hair, lotions or gels for combating hair loss, antiparasiticshampoos, etc.

[0048] The compositions according to the invention can also beformulated as solid preparations constituting cleansing bars or soaps.

[0049] The compositions comprising the compound of formula (I) can alsocomprise the product or active agent/species which can cause anirritation of the skin.

[0050] In this instance, the present invention also featurescompositions, preferably cosmetic, which comprise, formulated into aphysiologically acceptable medium, at least one compound of formula (I)and at least one product which can cause an irritation of the skin.

[0051] The amount of the at least one compound of formula (I) accordingto the invention is preferably a sufficient amount such that the skinirritant effect decreases, or even disappears. Thus, this amount can bevaried in particular as a function of the amount and of the nature ofthe product with an irritant nature which is applied. However, by way ofillustration, and as indicated above, a composition according to theinvention can comprise at least one compound of formula (I) at an amountranging from 0.001% to 30%, preferably from 0.01% to 20% and morepreferably still from 0.1% to 10%, of the total weight of thecomposition.

[0052] In the compositions according to the invention, the amount of theproduct which can cause an irritation of the skin can thus correspond toan amount which is sufficient to cause an irritation of the skin if itis present alone (without the compound of formula (I)).

[0053] The present invention presents, indeed, the advantage of beingable to increase the amount of active agents, which are conventionallyof irritant nature, in compositions with respect to the amount normallyemployed, with a view to improved effectiveness of the latter. Thus, theamount of active agent which can be used in the compositionadvantageously ranges from 5% to 50% of the total weight of thecomposition. In particular, it is possible to formulate hydroxy acids atup to 50% of the total weight of the composition, salicylic acid orderivatives thereof at up to 10%, or retinoids at up to 5%, without anydiscomfort for the user.

[0054] Many topically applied products have an irritant nature,especially for individuals (users) with skin which is easily irritated.Thus, these products, as described above, cause stinging, itching ortautness, which result in discomfort to the user which discouragesfurther use.

[0055] The products which can cause an irritation of the skin aretypically preservatives, surfactants, fragrances, solvents, propellantsand active agents, and mixtures thereof.

[0056] Thus, even the products which are considered to be inert in acosmetic composition can have an irritant nature when they are appliedto the skin, the scalp, the nails or the mucous membranes, such as, inparticular, preservatives, surfactants, fragrances, solvents orpropellants.

[0057] Too, products considered as active agents in cosmeticcompositions can have an irritant nature when they are applied to theskin, the scalp, the nails or the mucous membranes. This can be referredto as an irritant side effect exhibited by these products, which are, inparticular, active agents such as, especially, certain sunscreens,hydroxy acids, in particular α-hydroxy acids (glycolic, lactic, malic,citric, tartaric, mandelic, etc.) and β-hydroxy acids, especiallysalicylic acid and its derivatives, keto acids, in particular in α- andβ-form, derivatives of hydroxy or keto acids, especially in α- andβ-form, retinoids (retinol and its esters, retinal, retinoic acid andits derivatives, retinoids, in particular those described inFR-A-2570377, EP-A-0199636, EP-A-0325540 and EP-A-0402072), anthralins(dioxyanthranol), anthranoids (for example those described inEP-A-0319028), peroxides (in particular benzoyl peroxide), minoxidil andits derivatives, lithium salts, antiproliferating agents such as5-fluorouracil or methotrexate, certain vitamins such as vitamin D andits derivatives and vitamin B9 and its derivatives, hair tints or dyes(para-phenylenediamine and its derivatives, aminophenols), perfumingalcoholic solutions (fragrances, eaux de toilette, aftershave anddeodorants), antiperspirants (some aluminum salts), hair-removing orpermanent-waving active agents (thiols), depigmenting agents(hydroquinone), capsaicin, antilouse active agents (pyrethrin), ionicand nonionic detergent agents and propigmenting agents(dihydroxyacetone, psoralens and methylangecilins), and mixturesthereof.

[0058] Among vitamin D and derivatives thereof, particularly exemplaryas vitamin D₃, vitamin D₂, 1,25-dihydroxy vitamin D₃ (calcitriol),calcipotriol, 1,24-dihydroxy vitamin D₃ (such as tacalcitol),24,25-dihydroxy vitamin D₃, 1-hydroxy vitamin D₂ and 1,24-dihydroxyvitamin D₂.

[0059] Among the salicylic acid derivatives, particularly exemplary are5-n-octanoylsalicylic acid and 5-n-dodecanoylsalicylic acid, and theirsalts and esters thereof.

[0060] The present invention also features administering at least onecompound of formula (I) formulated into a nonirritant cosmeticcomposition or a cosmetic composition suited for individuals withsensitive skin.

[0061] The compositions which comprise at least one compound of formula(I) and at least one active agent which causes irritation of the skinare particularly suitable for caring for and/or for treating and/ormaking up human skin and/or mucous membranes and/or keratin fibers, andin particular for combating the signs of aging of the skin and/or forimproving the radiance of the complexion and/or for smoothing facialand/or body skin and/or for treating and reducing wrinkles and finelines on the skin and/or for stimulating the process of epidermalrenewal and/or for treating acne and/or for treating skinconditions/afflications.

[0062] Thus, this invention features the use of at least one compound offormula (I) in a cosmetic composition containing an active agent whichcauses irritation of the skin, destined for caring for human skin and/ormucous membranes and/or keratin fibers, and, in particular, intended forimproving the radiance of the complexion and/or smoothing facial and/orbody skin and/or combating the signs of aging of the skin and/or acne.

[0063] In addition, this invention features the manufacture orproduction of a dermatological or therapeutic composition containing atleast one compound of formula (I) and an active agent which causesirritation of the skin and which is suited for combating the signs ofaging of the skin and/or treating and reducing wrinkles and fine lineson the skin and/or stimulating the process of epidermal renewal and/ortreating acne and/or skin conditions.

[0064] By the term “skin conditions” are intended, in particular,shingles, burns, eczema, demodectic acariasis, skin ulcers, fibrosis,controlling healing, psoriasis, pruritus, dermatitis, ichthyosis, cornsand verrucae.

[0065] In order to further illustrate the present invention and theadvantages thereof, the following specific examples are given, it beingunderstood that same are intended only as illustrative and in nowiselimitative.

[0066] In said examples to follow, all parts and percentages are givenby weight, unless otherwise indicated.

EXAMPLE 1

[0067] Milk for the skin, having exfoliating activity:5-n-octanoylsalicylic acid 0.5% strontium 2,4-pentanedionate 0.5% BRIJ952.5% BRIJ92 2.5% liquid petroleum jelly 30% water qs 100%

[0068] The milk thus formulated was soft, had a good exfoliant propertyfor the skin and did not irritate the skin. It is well suited for use byindividuals with sensitive skin.

EXAMPLE 2

[0069] Test on Reconstructed Skin:

[0070] The Episkin system is a model of human epidermis reconstituted invitro, which was manufactured by the company Episkin. The epidermiscontained only one cell type: keratinocytes. The keratinocytes wereseeded onto a dermis equivalent which was composed of various types ofcollagen.

[0071] After a period of proliferation of the keratinocytes immersed inthe culture medium, the system was raised up to the air/liquidinterface. This step of immersing the cultures induced thedifferentiation of the keratinocytes towards the terminal stage ofcorneocytes in 13 days, thus allowing the reconstruction, in vitro, ofan epidermis which possessed a basal layer, a spiny layer, a granularlayer and a horny layer.

[0072] The assignee hereof has studied the cytotoxicity of thekeratinocytes (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide test) after applying to this reconstructed skin model variouscompositions in a proportion of 150 2 mg/cm, and maintaining same in anincubator at 37° C./5% CO₂ for a period of 18 hours. Each compositionwas tested on two epidermides of 1.13 cm .

[0073] The basic composition A was: BRIJ95 2.5% BRIJ92 2.5% liquidpetroleum jelly 30% water qs 100%

[0074] The other compositions tested corresponded to this composition Ato which 5-n-octanoylsalicylic acid, alone or in admixture with acompound of formula (I) according to the invention, was added.

[0075] The measurement of cell viability was carried out immediatelyafter rinsing of the compositions with phosphate buffered saline (PBS).

[0076] Thus, composition A was not cytotoxic. The addition of 0.3% (w/V)of 5-n-octanoylsalicylic acid to this composition rendered it cytotoxic.

[0077] The various compositions tested provided the results obtainedwhich are collated in the Table below: TABLE Concentration as % (w/V) ofConcentration the Compound of as % (w/V) of 5-n-octanoyl-salicylicformula (I) the compound of acid added to formula (I) added to % of cellcomposition A added composition A viability — 0 0.5 7.8 Strontium 2,4-0.54 0.5 95.5 pentanedionate Strontium 2,4- 0.8 0.75 125.6pentanedionate Strontium 2,4- 1.08 1 113.4 pentanedionate

[0078] The addition of a compound of formula (I) to composition A in thepresence of 0.5%, 0.75% or 1% of 5-n-octanoylsalicyclic acid did notrender the composition A cytotoxic.

[0079] While the invention has been described in terms of variousspecific and preferred embodiments, the skilled artisan will appreciatethat various modifications, substitutions, omissions, and changes may bemade without departing from the spirit thereof. Accordingly, it isintended that the scope of the present invention be limited solely bythe scope of the following claims, including equivalents thereof.

What is claimed is:
 1. A topically applicable cosmetic/dermatologicalcomposition for reducing mammalian skin irritation, comprising ananti-skin-irritant effective amount of at least one compound having theformula (I):

in which the radicals R, which may be identical or different, are each alinear or branched, saturated or unsaturated, optionally hydroxylatedalkyl or perfluoroalkyl radical having from 1 to 12 carbon atoms; theradicals R′, which may be identical or different, are each a linear orbranched, saturated or unsaturated, optionally hydroxylated alkyl,alkoxy or perfluoroalkyl radical having from 1 to 12 carbon atoms; and Xis magnesium, strontium, barium, zinc, manganese or palladium, saidcompound being in hydrated or nonhydrated form, and a topicallyapplicable, physiologically acceptable medium therefor.
 2. A compositionaccording to claim 1, wherein, in the compound of formula (I), eachradical R is a linear or branched, saturated alkyl or perfluoroalkylradical having from 1 to 6 carbon atoms.
 3. A composition according toclaim 1, wherein, in the compound of formula (I), each radical R′ is alinear or branched, saturated alkyl, alkoxy or perfluoroalkyl radicalhaving from 1 to 6 carbon atoms.
 4. A composition according to claim 1,wherein, in the compound of formula (I), R′ is a linear or branched,saturated alkyl, alkoxy or perfluoroalkyl radical having from 1 to 6carbon atoms.
 5. A composition according to claim 1, wherein, in thecompound of formula (I), the substituents R and R′ are linear.
 6. Acomposition according to claim 2, wherein, in the compound of formula(I), the substituents R and R′ are linear.
 7. A composition according toclaim 3, wherein, in the compound of formula (I), the substituents R andR′ are linear.
 8. A composition according to claim 4, wherein, in thecompound of formula (I), the substituents R and R′ are linear.
 9. Acomposition according to claim 1, wherein, in the compound of formula(I), the substituents R and R′ are saturated.
 10. A compositionaccording to claim 2, wherein, in the compound of formula (I), thesubstituents R and R′ are saturated.
 11. A composition according toclaim 1, wherein, in the compound of formula (I), the substituents R andR′ comprise a difference of at most two carbon atoms with respect toeach other.
 12. A composition according to claim 2, wherein, in thecompound of formula (I), the substituents R and R′ comprise a differenceof at most two carbon atoms with respect to each other.
 13. Acomposition according to claim 3, wherein, in the compound of formula(I), the substituents R and R′ comprise a difference of at most twocarbon atoms with respect to each other.
 14. A composition according toclaim 4, wherein, in the compound of formula (I), the substituents R andR′ comprise a difference of at most two carbon atoms with respect toeach other.
 15. A composition according to claim 1, wherein, in thecompound of formula (I), X is strontium or zinc.
 16. A compositionaccording to claim 2, wherein, in the compound of formula (I), X isstrontium or zinc.
 17. A composition according to claim 3, wherein, inthe compound of formula (I), X is strontium or zinc.
 18. A compositionaccording to claim 4, wherein, in the compound of formula (I), X isstrontium or zinc.
 19. A composition according to claim 5, wherein, inthe compound of formula (I), X is strontium or zinc.
 20. A compositionaccording to claim 6, wherein, in the compound of formula (I), X isstrontium or zinc.
 21. A composition according to claim 7, wherein, inthe compound of formula (I), X is strontium or zinc.
 22. A compositionaccording to claim 8, wherein, in the compound of formula (I), X isstrontium or zinc.
 23. A composition according to claim 9, wherein, inthe compound of formula (I), X is strontium or zinc.
 24. A compositionaccording to claim 10, wherein, in the compound of formula (I), X isstrontium or zinc.
 25. A composition according to claim 11, wherein, inthe compound of formula (I), X is strontium or zinc.
 26. A compositionaccording to claim 12, wherein, in the compound of formula (I), X isstrontium or zinc.
 27. A composition according to claim 13, wherein, inthe compound of formula (I), X is strontium or zinc.
 28. A compositionaccording to claim 14, wherein, in the compound of formula (I), X isstrontium or zinc.
 29. A composition according to claim 1, wherein, inthe compound of formula (I), R and R′ are methyl radicals.
 30. Acomposition according to claim 15, wherein, in the compound of formula(I), R and R′ are methyl radicals.
 31. The composition according toclaim 1, wherein said at least one compound of formula (I) is selectedfrom the group consisting of strontium 2,4-pentanedionate,bis(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionato)strontiumhydrate, bis(2,2,6,6-tetramethyl-3,5-heptanedionato)strontium hydrateand strontium hexafluoroacetylacetonate and mixtures thereof.
 32. Atopically applicable cosmetic/dermatological composition forsubstantially inhibiting or reducing mammalian skin irritation,comprising an irritant amount of at least one normally skin-irritatingactive species/product and an anti-irritant effective amount of at leastone compound having the formula (I):

in which the radicals R, which may be identical or different, are each alinear or branched, saturated or unsaturated, optionally hydroxylatedalkyl or perfluoroalkyl radical having from 1 to 12 carbon atoms; theradicals R′, which may be identical or different, are each a linear orbranched, saturated or unsaturated, optionally hydroxylated alkyl,alkoxy or perfluoroalkyl radical having from 1 to 12 carbon atoms; and Xis magnesium, strontium, barium, zinc, manganese or palladium, saidcompound being in hydrated or nonhydrated form, and a topicallyapplicable, physiologically acceptable medium therefor.
 33. Acomposition according to claim 32, wherein, in the compound of formula(I), each radical R is a linear or branched, saturated alkyl orperfluoroalkyl radical having from 1 to 6 carbon atoms.
 34. Acomposition according to claim 32, wherein, in the compound of formula(I), each radical R′ is a linear or branched, saturated alkyl, alkoxy orperfluoroalkyl radical having from 1 to 6 carbon atoms.
 35. Acomposition according to claim 32, wherein, in the compound of formula(I), the substituents R and R′ are linear.
 36. A composition accordingto claim 32, wherein, in the compound of formula (I), the substituents Rand R′ are saturated.
 37. A composition according to claim 32, wherein,in the compound of formula (I), the substituents R and R′ comprise adifference of at most two carbon atoms with respect to each other.
 38. Acomposition according to claim 32, wherein, in the compound of formula(I), X is strontium or zinc.
 39. A composition according to claim 32,wherein, in the compound of formula (I), R and R′ are methyl radicals.40. A composition according to claim 38, wherein, in the compound offormula (I), R and R′ are methyl radicals.
 41. The composition accordingto claim 32, wherein said at least one compound of formula (I) isselected from the group consisting of strontium 2,4-pentanedionate,bis(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionato)strontiumhydrate, bis(2,2,6,6-tetramethyl-3,5-heptanedionato)strontium hydrateand strontium hexatluoroacetylacetonate and mixtures thereof.
 42. Acomposition according to claim 32, wherein said at least one normallyskin-irritating active species/product is selected from the groupconsisting of a preservative, surfactant, fragrance, solvent,propellant, active agent, and mixtures thereof.
 43. A compositionaccording to claim 32, wherein said at least one normallyskin-irritating active species/product is selected from the groupconsisting of a sunscreen, hydroxy acid, keto acid, retinoid, anthralin,anthranoid, peroxide, minoxidil, lithium salt, antiproliferating agent,vitamin, hair tint, hair dye, perfuming alcoholic solution,antiperspirant, hair-removing active agent, permanent-waving activeagent, depigmenting agent, capsaicin, antilouse active agent, ionicdetergent agent, nonionic detergent agent, propigmenting agent andmixtures thereof.
 44. A composition according to claim 32, wherein saidat least one normally skin-irritating active species/product is selectedfrom the group consisting of an α-hydroxy acid, a β-hydroxy acid, anα-keto acid, a β-keto acid, 5-fluorouracil, methothrexate, vitamin B9,vitamin D or a derivative thereof and mixtures thereof.
 45. Acomposition according to claim 32, wherein said at least one normallyskin-irritating active species/product is a p-hydroxy acid.
 46. Acomposition according to claim 32, wherein said at least one normallyskin-irritating active species/product is salicylic acid or a derivativethereof.
 47. A composition according to claim 32, wherein said at leastone normally skin-irritating active species/product is selected from thegroup consisting of 5-n-octanoylsalicylic acid, 5-n-dodecanoylsalicylicacid, a salt thereof, and an ester thereof.
 48. A composition accordingto claim 1, which is in liquid form.
 49. A composition according toclaim 1, which is selected from the group consisting of an oilysolution, gel, anhydrous liquid, anhydrous solid, anhydrous paste,emulsion, microemulsion, vesicular dispersion, cream, lotion, milk,ointment, serum, mousse, aerosol, stick, makeup, shampoo and soap.
 50. Acomposition according to claim 49, which is other than a cream or soap.51. A composition according to claim 32, which is in liquid form.
 52. Acomposition according to claim 32, which is selected from the groupconsisting of an oily solution, gel, anhydrous liquid, anhydrous solid,anhydrous paste, emulsion, microemulsion, vesicular dispersion, cream,lotion, milk, ointment, serum, mousse, aerosol, stick, makeup, shampooand soap.
 53. A composition according to claim 52, which is other than acream or soap.
 54. A composition according to claim 1, wherein said atleast one compound of formula (I) is present in an amount of from 0.001%to 30% by weight of the total weight of the composition.
 55. Acomposition according to claim 1, wherein said at least one compound offormula (I) is present in an amount of from 0.01% to 20% by weight ofthe total weight of the composition.
 56. A composition according toclaim 1, wherein said at least one compound of formula (I) is present inan amount of from 0.1% to 10% by weight of the total weight of thecomposition.
 57. A composition according to claim 32, wherein said atleast one compound of formula (I) is present in an amount of from 0.001%to 30% by weight of the total weight of the composition.
 58. Acomposition according to claim 32, wherein said at least one compound offormula (I) is present in an amount of from 0.01% to 20% by weight ofthe total weight of the composition.
 59. A composition according toclaim 32, wherein said at least one compound of formula (I) is presentin an amount of from 0.1% to 10% by weight of the total weight of thecomposition.
 60. A composition according to claim 32, wherein said atleast one normally skin-irritating active species/product is present inan amount of from 5% to 50% by weight of the total weight of thecomposition.
 61. A composition according to claim 57, wherein said atleast one normally skin-irritating active species/product is present inan amount of from 5% to 50% by weight of the total weight of thecomposition.
 62. A composition according to claim 58, wherein said atleast one normally skin-irritating active species/product is present inan amount of from 5% to 50% by weight of the total weight of thecomposition.
 63. A composition according to claim 59, wherein said atleast one normally skin-irritating active species/product is present inan amount of from 5% to 50% by weight of the total weight of thecomposition.
 64. A composition according to claim 1, wherein thecompound of formula (I) is the product of the reaction of a β-diketoneand a hydroxylated or carbonated activated cation.
 65. A compositionaccording to claim 32, wherein the compound of formula (I) is theproduct of the reaction of a P-diketone and a hydroxylated or carbonatedactivated cation.